Jacking structure for towers



Nov. 21, 19 50 E. A. CAMPBELL ,3

JACKING STRUCTURE FOR TOWERS Filed Oct. 31, 1949 5 Sheets-Sheet 1 aiINVENTOR.

Nov. 21, 1950 E. A. CAMPBELL JACKING STRUCTURE FOR TOWERS 5 Sheets-Sheet 2 Filed Oct. 31, 1949 INVENTOR.

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JACKING STRUCTURE FOR TOWERS Filed 001.. 31, 1949 5 Sheets-Sheet 3 ENTOR.

Q46 U 21g. 3 BY m'/wawfi w flaanh E. A. CAMPBELL JACKING STRUCTURE FOR TOWERS Nov. 21, 1950 5 Sheets-Sheet 4 Filed 001;. 31. 1949 Nov. 21, 1950 E. A. CAMPBELL JACKING STRUCTURE FOR TOWERS Filed Oct. 31 1949 5 Sheets-Sheet 5 the center of the frame. The rails are connected at vertically spaced intervals by horizontal braces l3 that curve outward away from the rails. The lower part of the frame is further braced by a pair of tubular braces l4 welded to the base member l2 and converging upward and outward to one of the horizontal braces [3.

Located between the side rails of the frame is a pair of long parallel screws It, the upper ends of which extend up through the crossbeam at the top of the frame. Heads I? are secured to the projecting upper ends of the screws, these heads being rotatably-mounted in and supported by bearings I8 mounted on top of the beam. The screws are thus suspended in the frame from their upper ends. The lower end of each screw extends down into the hollow base member l2 where it is splined in a worm gear I9 (Fig. 11) journaled in a box 2| mounted in the base member. Each gear meshes with a worm '22 on a shaft 23 that extends out through the front of the base member and through a bracket 24 attached to the top of that member. Between the base member and bracket, each shaft supports a sprocket 28 around which a chain 21 extends. The outer end of one shaft carries a hand wheel 28, by which the shaft can be turned, whereupon the other shaft will be turned with it by means of the chain and sprockets, so that the two screws are rotated in unison.

The base of each frame is designed to rest on top of a frame support formed from spaced inner and outer horizontal supporting beams 38 and 3|, as shown in Figs. 6 and '7. The frame is provided with a pair of depending lugs 32 that will project down between the two supporting beams, where they are locked in place by removablepins 33 inserted through openings in the lugs, inner channel beam 38, and a vertical plate 34 welded in the back of outer I beam 3!. The two beams are detachably connected together at their ends by brackets 36 secured to plate 36. Supporting beams 38 and SI are intended to be clamped to a leg stub 2 just below the splice. For this purpose the inner beam is secured to an inclined clamping member 3? adapted to fit inside of a leg stub. The outer beam is provided with a similar clamping member 38 adapted to fit over the outside of the stub. The two clamping members are bolted to the stub between them before the jack frame is set on the frame support.

The actual lifting of each tower leg is done by means of a lifting member 48 attached to the leg and to the screws It} in the adjoining jack. As best shown in Figs. 5, '7 and 10, the lifting member has parallel side walls 4| connected along their upper edges by a top plate 42. The ends of this plate are provided with holes through which the jack screws extend. Rigidly mounted in opposite ends of the lifting member are nuts 43 which are threaded on the screws, so that when the screws are turned the lifting member will be moved vertically thereby. To guide the lifting member and to help relieve the screws of lateral strains, the opposite ends of the lift ing member carry guide rollers 44 that engage the converging surfaces of the adjoining side rails Ill of the jack frame. Each roller is journalled on a bolt 46 screwed into an in-turned end of one of the side walls of the lifting member. The outer end of the bolt is supported by a bracket 4'! welded to a side of the lifting member.

The lifting member is attached to leg section I above the splice by means of a clamp 48 which is shaped to fit over the outer surface of the leg.

4 The outer part of the clamp has a projection that extends upward into the lifting member, and the projection is provided with a transverse hole through which a pivot pin 49 extends. The ends of the pin also extend through holes in a pair of parallel vertical plates 50 Welded to the opposite sides of the lifting member. This pivotal suspension of the clamp from the lifting member prevents the clamp from causing the lifting member to bind on the rails l8 and the screws in case there is any lateral movement of the leg relative to the jack.

When itis desired to raise a tower, such as shown in Fig. 1, an excavation first is made around each tower leg so that there will be room to attach the frame supports to the legs below the splices where the upper and lower leg sections I and 2 are joined. Bolt holes are then drilled in each leg stub below the splice, and additional bolt holes are drilled in each leg above the splice. These holes permit the clamps of the jacks to be attached to the legs. The next step is to bolt clamping members 37 and 38 to each leg stub 2 and to bolt clips 36 to inner framesupporting beam 39. With the frame supports thus attached to the leg stubs, a jack column or frame is set on each frame support with its lugs 32 projecting down between the two beams of the support. Locking pins 33 are driven through the two beams and lugs to lock the frame on the support. .Fig. 1 shows the frame supports attached to the legs, and a jack frame mounted on one of the supports. After all of the jacks have been placed in position, the lifting leg clamps 48 are bolted to legs I above the splices.

The next operation is to rigidly connect the four jack frames together around the tower by means of horizontal girts 53 and inclined braces 55, as shown in Fig. 2. Additional braces are added later, after certain interfering braces on the tower have been removed, as now will be described. First, the lower sections of inclined braces 6 of the tower must be removed, one of these being removed at a time and replaced immediately by an inclined brace 5") connecting the leg stub to the lowest girt of the jacking structure. The hand wheels 28 of the four jacks then are turned to apply a lifting force to the tower sufficient to relieve the load at the leg splices, whereupon the splice bolts can be removed. These bolts are removed from only one face of the tower at a time, and new gusset plates 5! are welded to the lower ends of the upper leg sections l. Horizontal girts 5, inclined braces 8 and supplementary braces 58 and 59 then are removed from the same tower face and are replaced immediately by inclined braces El connected to the new gusset plates, and by substantially horizontal girts 62. Also, a lower girt 63 is added which has a vertical brace 64 extending from its center up to the point where the inclined braces 6| cross. Diagonal braces 56 (Fig. 4) also are added to connect the lower ends I of leg sections I. Braces 66 and girts 53 tie the lower ends of leg sections I together. The jacks are then operated again to raise the tower about one foot, as shown in Fig. 2. Diagonal braces 61 (Figs. 2 and 4) then can be installed in the lower part of the jacking structure to reiniseases:

until they have reached the desired height. A. tower extension NJ, as shown in Fig. 3-, thenv is erected inside the jacking. structure in thespace between the leg stubs 2 and the bottom of the elevated tower. This extension includes verticaliextension legs i i connected to the upper ends of the leg stubs and to the lower ends of legs I The extension. legs also are connected by inclined braces T'Zto the leg stubs. Horizontal girts 13 help strengthen the extension. After the ex tension has been erected, the jacks are operated to lower, the lifting mmbers 49. just. enough to take the strain off lifting clamps 48 so that they can be disconnected from leg sections l. The jacking structure braces are removed next, and then the jack frames are removed from their supports. Following this, the frame supports are disconnected from the leg stubs and the excavations around the stubs are filled in. Fig. 3 shows extension 19 in place and all of the jacking structure,.except one jack, removed from the tower.

The. height of the tower has been increased by the height of the extension.

When jack screws of the great length (twenty feet) necessary here are used, they must always remainunder tension while the load is on them. Otherwisathey would buckle or would have to have; a very great diameter to support a compression load. The screws IE shown herein are always under tension because they are suspended from their. upper ends, while their lower ends are splined inworm gears l9 so that no resistance will be, offered to stretching of the screws when theload is on them.

According to the provisions of the patent statutes, I have explained the principle of my invention and have illustrated and described what I now consider to represent its best embodiment. However, I desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

I, claim:

1. A jacking structure for a tower provided with a plurality of legs, said structure comprising a separate, jack for each tower leg and braces for rigidlyconnecting the jacks together around the tower; each jack including a Vertical frame, means adapted to connect the lower end of the frame to a tower leg near the surface of the ground to support the frame from said leg, a vertical screw rotatably mounted at its upper end in the top of the frame and suspended therefrom, means mounted in one end of the frame for rotatingthe screw, a lifting member threaded on the screw for vertical travel when the screw is turned, and means adapted to connect said lifting member to said tower leg, whereby after the leg has been separated into two sections at a point between the lifting member and the lower end'of the frame the upper section of the leg can be raised.

2. A jacking structure for a tower providedwith a plurality of legs, said structure comprising a separate jack for each tower leg and braces for rigidly connecting the jacks together around the tower; each jack including a vertical frame, a support for the lower end of the frame-adapted to be fastened to a tower leg near the surface of the ground, a pair of parallel vertical screws rotatably mounted at their upper ends in the top of the frame and suspended therefrom, means mounted inone end of the frame for rotating the two screws in unison, a lifting member threaded on both screws for vertical travel when they are turned, and means adapted to comiect said lifting member to. said tower leg, whereby after the leg. has beenseparated into two sections at a point between the lifting memher and said support theuppersection of the leg.

can be raised.

3; A jacking structure for a tower provided with a plurality of legs, said structure comprising a separate jackv for each tower leg and.

braces for rigidly connecting the jacks together around the tower; each jack includinga vertical frame, means adapted to connect the lower end ofthe-frame to a tower leg near the-surface of the-ground to support the frame from said leg, a vertical screw rotatably mounted at its upper end in the top of the frame and suspended therefrom, means mounted in the lower end of the frame for rotating the screw, a lifting member threaded on thescrew for vertical travel when the screw is turned, a clamp adapted to be fastened to said tower leg, and means for pivotally connectingsaid clamp to thelifting member on a horizontal axis extending across said leg, whereby. after the leg has been separated into two sections at a point between the clamp and the lower end of the frametheupper section of the leg can be raised.

4; A jacking structure for a towerprovided with a plurality of legs, said structure com-- prising a separate jack for each tower leg and braces for rigidily connecting the jacks together around the tower; each jack including a vertical-frame having parallel sides, means adapted to connect the lower end of the-frame to a tower leg near thesurface of the ground to support the-framefrom said leg, a vertical screw rotatably mounted at its upper end in the top of the frame and suspended therefrom, mean mounted in the lower end of the frame for rotating the screw, a lifting member threaded on the screw for vertical travel when the screw is turned, rollers carried by said member and engaging said sides of the frame for guiding the lifting member, and means adapted to connect said lifting member to said tower leg, whereby after the leg has been separated into two sections at a point between the lifting member and the lower end of the frame the upper section of the leg can be raised.

5. A jacking structure for a tower provided with a plurality of legs, said structure comprising a separate jack for each tower leg and braces for-rigidly connecting the jacks together around the tower; each jack including a vertical frame having parallel side rails, each of said rails having a pair of side surfaces converging toward the center of the frame, means adapted to connect the lower end of the frame to a tower leg near the surface of the ground to support the frame from said leg, a pair of parallel vertical screws rotatably mounted in the top of the frame and suspended therefrom, means mounted in the lower end of the frame for rotating the two screws in unison, a lifting member threaded on both screws for vertical travel when they are turned, a pair'of rollers carried by each end of said member in engagement with said converging surfaces ofthe adjoining side rail for guiding the lifting member, and means adapted to connect said lifting member to said tower leg, whereby after the leg has been separated into two sections at a point between the lifting memberand the lower end of the frame the upper section of the leg can be raised.

6. A jacking structure for a tower provided with a plurality of'legs, said structure comprising a separate jack for each tower leg and braces for rigidly connecting the jacks together around the tower; each jack including a vertical frame having parallel side rails, each of said rails having a pair of side surfaces converging toward the center of the frame, a support for the lower end of the frame, a clamp adapted to be fastened to a tower leg near the surface of the ground to support said frame support, a pair of parallel vertical screws suspended and rotatably mounted in the top of the frame and suspended therefrom, means mounted in the lower end of the frame for rotating the two screws in unison, a lifting member threaded on both screws for vertical travel when they are turned, a pair of rollers carried by each end of said member in engagement with said converging surfaces of the adjoining side rail for guiding the lifting member, and a clamp adapted to be fastened to said tower leg and suspended from said lifting member between said screws, whereby after the leg has been separated into two sections at a point between the two clamps the upper section of the leg can be raised.

7. A jacking structure for a tower provided with a plurality of legs, said structure comprising a separate jack for each tower leg ad braces for rigidly connecting the jacks together around the tower; each jack including a vertical frame, a support for the lower end of the frame adapted to be fastened to a tower leg near the surface of the ground, a pair of parallel vertical screws rotatably mounted at their upper ends in the top of the frame and suspended therefrom, worm gears rigidly mounted on the lower ends of the screws, parallel worms meshing with said gears, means for turning one of the worms, sprockets rigidly connected to both worms, a chain connecting the sprockets so that both screws will be turned in unison, a lifting member threaded on both screws for vertical travel when they are turned, and means adapted to connect said lifting member to said tower leg, whereby after the leg has been separated into two sections at a point between the lifting member and the lower end of the frame the upper section of the leg can be raised.

8. A jacking structure for a tower provided with a plurality of legs, said structure comprising a separate jack for each tower leg and braces for rigidly connecting the jacks together around the tower; each jack including a vertical frame, a support for the lower end of the frame, a clamp adapted to be fastened to a tower leg near the surface of the ground for supporting said frame support, means for detachably mounting the frame on said support, a vertical screw rotatably mounted at its upper end in the top of the frame and suspended therefrom, means mounted in the lower end of the frame for rotating the screw, a lifting member threaded on the screw for vertical travel when the screw is turned, and means adapted to connect said lifting member to said tower leg, whereby after the leg has been separated into two sections at a point between the lifting member and the clamp the upper section of the leg can be raised.

9. A jacking structure for a tower provided with a. plurality of legs, said structure comprising a separate jack for each tower leg and braces for rigidly connecting the jack together around the tower; each jack including a vertical frame, inner and outer clamping members adapted to be fastened to the inner and outer surfaces of a tower leg near the surface of the ground, inner and outer horizontal beams rigidly mounted on said clamping members, means detachably connecting said beams together in laterally spaced relation, the lower end of the frame being provided with a depending projection inserted between said beams with the frame resting on them, a fastening member extending through said beams and frame projection to detachably hold the frame on the beams, a pair of parallel vertical screws rotatably mounted at their upper ends in the top of the frame and suspended therefrom, means mounted in the lower end of the frame for rotating the two screws in unison, a lifting member threaded on both screws for vertical travel when they are turned, and means adapted to connect said lifting member to said tower leg, whereby after the leg has been separated into two sections at a point between the lifting member and said clamping members the upper section of the leg can be raised.

10. A jacking structure for a tower provided with a plurality of legs, said structure comprising a separate jack for each tower leg and braces for rigidly connecting the jacks together around the tower; each jack including a vertical frame having parallel side rails, inner and outer clamping members adapted to be fastened to the inner and outer surfaces of a tower leg near its lower end, inner and outer horizontal beams rigidly mounted on said clamping members, means detachably connecting said beams together in laterally spaced relation, the lower end of the frame being provided with a depending projection inserted between said beams with the frame resting on them, a fastening member extendin through said beams and frame projection to detachably hold the frame on the beams, a pair of parallel vertical screws rotatably mounted at their upper ends in the top of the frame and suspended therefrom, means mounted in the lower end of the frame for rotating the two screws in unison, a lifting member threaded on both screws for vertical travel when they are turned, rollers carried by said member and engaging said side rails of the frame for guiding the lifting member, a clamp adapted to be fastened to said tower leg above said clamping members, and means for pivot-ally connecting said clamp to the lifting member on a horizontal axis extending across said leg, whereby after the leg has been separated into two sections at a point between said clamp and said clamping members the upper section of the leg can be raised.

11. A jacking structure for a tower provided with a plurality of legs, said structure comprising a separate jack for each tower leg and braces for rigidly connecting the jacks together around the tower; each jack including a vertical frame, means connected to the lower end of the frame for supporting it, a vertical screw rotatably mounted at its upper end in the top of the frame and suspended therefrom, means mounted in one end of the frame for rotating the screw, a lifting member threaded on the screw for vertical travel when the screw is turned, and means adapted to connect said lifting member to said tower leg, whereby after the leg has been separated into two sections at a point below the "10 lifting member the upper section of the leg can be raised.

ERWIN A. CAMPBELL.

No references cited. 

